Download DNA-RNA-Protein Practice Hwk

IB Biology Year 1
Name: __________________________________________ Per. _____
DNA, RNA, Protein Practice
Directions: respond to these questions in the spaces provided.
1.
How do the data in the table at the right demonstrate
Chargaff's rules?
2.
In DNA replication, what is the biochemical basis for the difference in how the leading strand of DNA is
synthesized relative to the lagging strand?
3.
Lysine and arginine make up more than 20% of histone proteins' amino acids. Given the structure of DNA, why
is this expected? Hint: see the amino acid chart in Chapter 5 -- figure 5.16.
4.
In Chapter 17, figure 17.4, compare the sequence of the messenger RNA (in red) to that of the nontemplate DNA
strand (reading from the 5' to 3' direction). What do you notice?
5.
Neil uses "translator" as a metaphor for the function of a transfer RNA (tRNA) molecule. We use "adaptor plug."
Come up with your own metaphor for tRNA and explain how it works.
6.
ON THE BACK OF THIS PAGE where you have more room, make a T-chart to compare and contrast codons with
anticodons. Make your comparisons structural and/or functional, and significant. Be professional; use a ruler.
7.
Which of the following is not directly involved in translation? After circling the one not involved, write a brief
description of the roles of each of the 4 entities that are directly involved in translation.
DNA
___________________________________________________________________________________________
GTP (chemical cousin of ATP) __________________________________________________________________________________________
mRNA ___________________________________________________________________________________________
ribosome ___________________________________________________________________________________________
tRNA ___________________________________________________________________________________________
8.
Knowing that the genetic code is virtually universal, a scientist uses biotechnology methods to insert a human
gene into bacterial cells, hoping the cells will express it and synthesize functional human protein. Instead, the
protein produced is found to contain many fewer amino acids than the actual protein made by a eukaryotic cell,
and doesn't work. What could have gone wrong? As you did for # 6, please answer on the back!